An electric power system is a network of electrical components deployed that generates, transfers, optionally stores, and uses electrical power. An electric power system comprises power generator(s), transmission lines, and various customers (or “loads”). Power received from the power generator(s) is transferred to various loads over the transmission lines that includes transformers therein.
A ‘power grid’ as used herein is an interconnected network within the power system used for transmission and distribution of power from the power generator(s) including the power lines and the transformers to the loads. The power generators can include coal and natural gas-burning power plants, hydroelectric dams, nuclear power plants, wind turbines, and solar panels which all generate electrical power. Power grids are designed and controlled to be run at a single frequency and to supply voltages at largely constant amplitudes which is achieved with varying load demand, including variable reactive loads, and even nonlinear loads, with electricity provided by power generators and distribution and transmission equipment such as transmission lines that may not always be reliable.
Power outages in locations throughout the world including in the United States (US) is becoming a commonplace event due to the increase in both frequency and strength of natural disasters. Another threat to power grids is cyberattacks. For instance, in 2012, hurricane Sandy devastated the power grid along the northeast coast of the US, leaving more than 8 million people without power for over a week. Power outages cost industries and businesses in the US billions of dollars and can jeopardize the lives of hospital patients. According to the Electric Power Research Institute, across all business sectors the US economy loses over 150 billion dollars a year due to power outages.
Power system operators are currently guided by a series of power restoration plans prepared offline based on a set of power outage (or blackout) scenarios. Major independent system operators (ISOs) in the US provide restoration manuals to guide operators to deal with disturbance conditions or after a power outage. Offline restoration plans are developed to assist power system operators to bring the power back online after a major power outage. However, the offline restoration plans need to be constantly checked against system conditions that can change over time. As a result, recovery of the power grid from a power outage is often prolonged and power system operators can face tremendous pressure. Moreover, unexpected events can occur during the restoration process, such as the loss of power generator(s) or transmission lines, imposing further challenges for power grid restoration.